The latest estimated resident population data for regions and districts published by Statistics New Zealand (Stats NZ) in late October threw up a few surprises, not least that Auckland’s population is a lot lower than previously estimated. Indeed, we have been overestimating population in many of our larger urban centres and underestimating it in the smaller provincial districts.

Stats NZ’s recent Estimated Resident Population release included new estimates for the year to June 2019 and revisions to their previous 2018 estimates. The revisions incorporate Stats NZ’s better understanding of international net migration, which sees the 2018 total NZ population revised down by about 44,000, and some of the preliminary subnational findings from the 2018 census.

Auckland saw a massive reduction of 77,500 people to its 2018 estimated population in the October 2019 release compared to the estimates released in late 2018. This is almost equivalent to the urban population of Palmerston North and represents a 4.6% downward revision in Auckland’s population (view map).

Auckland planners will be scratching their heads after discovering that the population in the Auckland CBD did not grow by 23,000 between 2013 and 2018, as was previously estimated by Stats NZ. Instead, the new figures from Stats NZ suggest it grew by less than 3,000 over the five years to June 2018 (see Chart 1).

Many other major urban centres experienced downward revisions to their 2018 population estimates, including Christchurch (-8,300), Wellington City (-7,300), Hamilton (-3,400), and Palmerston North (-1,400).

In contrast to Auckland CBD’s growth of 3,000, Whanganui’s population grew by 3,200 over the five-year period according to the new estimates. This trend is true for the population of many of New Zealand’s smaller provincial districts, which were revised upwards and are showing healthy growth. The revisions suggest that there has been more outward migration from Auckland to the provinces than we previously thought.

Among the 67 territorial authorities in New Zealand, 63 of them experienced population growth over the year to June 2019. Only Buller and Waitomo Districts experienced a decline in population, while Hurunui and Grey’s population remained unchanged. By contrast, over the year to 2009, there were 21 territorial authorities that experienced no annual population growth, showing just how far the regions have come.

Tauranga was the local council area with the largest revision in population between the old and new estimates. New estimates have taken Tauranga’s population up to 140,000, which is higher by 5,800 people than was previously thought. Hastings had the second-largest upward revision, up 3,400, followed by Far North and Western Bay of Plenty, both up 2,800 (see Chart 2).

Overall, the 55 areas that recorded an increase added up to 54,660 more people in total, with 22 areas having an upwards revision of 1,000 people or more.

In total, downwards revisions added up to a reduction of almost 99,000 people, with 77,500 in Auckland alone. Combined with the increased population of around 54,000 people across the areas with upward revisions, the net effect was a reduction in New Zealand’s estimated population of around 44,000 people for June 2018.

A full breakdown of the original and revised subnational population estimates for 2018, along with 2019 estimates, is available here for each local council area in New Zealand.

The current sub-national Estimated Resident Population series from Stats NZ does not include data for the years 2014 to 2017. Infometrics has estimated a series for these years and will be publishing it in our Regional Economic Profiles on 15 November 2019.

The Infometrics series will be in place until March 2020 when Stats NZ will release a complete time series of subnational population data which will fully include the Census 2018 data which will have been adjusted for the census undercount.

Sub-national population projections, based on the 2018 census and consistent with the revised subnational population estimates, will not become available from Stats NZ until December 2020. In the absence of updated official projections, Infometrics is able to provide projections out to 2050 for clients by early next year – please contact Nick Brunsdon for more information.

At current, there are four broad sets of subnational population data either available or coming soon. The table below outlines what each set of figures includes or excludes.

(P) = Provisional

*Stats NZ advise that the subnational population estimates are apportioned according to the subnational distribution of the 2018 Census counts. The revised estimates at 30 June 2018 (released October 2019) reflect the size and age/sex structure of the 2013-base national population estimate, and the subnational distribution of the 2018 Census counts.